Telephone central station apparatus



N0. 6l2,2l9. Patented 00f. ll, 1898. J. H. WEST.

TELEPHONE CENTRAL STATHJN APPARATUS.

(Application filed. July 8, 1896.)

BY gram/5y:

NITED STATES JULIUS HENRIK VEST,

PATENT OFFICE.

OF BERLIN, GERMANY.

SPECIFICATION forming part of Letters Patent No. 612,219, dated October 11, 1898.

Application filed July 8,1896. Serial No. 598,447. (No model.) Patented in France May 7, 1896, No. 256,178; in Switzerland June 4, 1896,1To. 12,273; in England June 5, 1896,110. 12,344; in Hungary Tune 6,1896,No. 7,863, and in Austria.

September 2,1896,N0. LG/3,390.

T 0 all whom it may concern: 1

Be it known that I, JULIUS HENRIK Wnsr, a subject of the King of Denmark, residing at Berlin, in the German Empire, have invented a certain new and useful Telephone Central-Station Apparatus, (patented in England, No. 12,344, June 5, 1896; in France, No. 256,178, May 7, 1896; in Austria, No. 46/3390, September 2, 1896; in Hungary, No. 7,863, June 5, 1896, and in Switzerland, No. 12,273, June 4, 1896;) and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

This invention has for its object to provide an improved apparatus for the simplification of the working of telephone-stations in which each line can be engaged at several pointsthat is, at either section of a multiple switchboard-so that it is necessary to have means whereby the operatoiybefore connecting a line, can ascertain'whether the said line is possibly already engaged.

On the accompanying drawings, Figure 1 shows a diagram of mysystem. Fig. 2 is a longitudinal section of a switch-plug, and Fig. 3 is a front View of a lamp-chamber.

Two subscribers lines T and '1 are shown running through three multiple switchboards I II III of a station. To the right hand is a glow-lamp board G T, consisting of a framin g formed of metal bars effectually insulated from earth. A number of glow-lamps g 9?, corresponding to the number of subscribers, are fixed 011 the base in such manner that the one pole thereof is in conducting connection with'the bar, while the other pole is con;

nected to an insulated contact (1 of the corresponding indicator and with the spring f of connected to the glow-lamp. The night callbell TV is introduced if H is turned on to contact '3'.

Generally H is on contact 2. As will be readily seen in Fig. l, the lamp will light up as soon as the shutter of annunciator K falls at the call of a subscriber, as the spring f bears against the contact (1, thereby closing the circuit from the lamp g to the battery B, causing the ,lamp to glow. If the operator then introduces the plug 3 (shown at Fig. 2) of the connecting-cord intothejack 7c of the switchboard I, the ring a of the plug will et- 1 feet the closing of a second circuit, through the springs f and f to the battery from the lamps 9. Consequently when the operator raises the shutter of annunciator K again the lamp will continue to glow as long as the plug remains in the jack If a subscriberforinstance, T is called, his glow-lamp will light up at the moment when a plug is inserted in one of his jacks W, and it will continue to glow until the plug is withdrawn e., as long as the line is occupied.

It will be seen that there are two circuitcontrolling devices for the circuit of each lamp at the section of the multiple switchboard at which the corresponding telephoneline has an annunciator-namely (1) at such annunciator, and (2) at the spring-jack of said telephone-line; but at each other section of the multiple switchboard the circuit of said lamp has a single controlling device only-namely, at the spring-jack of the same telepho11e-lineand consists of springs f f and ring 7' of a switch-plug.

The glow-lamp board is so arranged that it can be readily seen from all the switchboards, so that each operator can see at a moment from the lamp-board when a connection is desired whether the required line is engaged or not. In large stations several of such lamp-boards may be provided. 7

It will be evident that the converse arrange ment could be adopted, whereby on the falling of the shutter and on inserting a plug the lamp-circuit is interrupted, so that the lighting up of the lamp then indicates that the line is free and the extinguishing thereof that the line is engaged.

Having now particularly described and ascertaincdthe nature of my said invention and in what manner the same is to be performed, I declare that what I claim is 1. The combination of telephone lines, spring-jacks therefor at several switchboards to which thelines are connected, an ann unciator for each line and normally connected therein, a visual indicating-signal for each line, one terminal of each indicating-signal being. normally connected to a source of electricity, the other terminal being connected to two circuit-controlling devices, one controlled by the operation of an annunciator, the other forming a part of a spring-jack, being controlled by insertion of a plug in said jack.

2. The combinatiomwithsubscriberslines, multiple switchboards each having a jack for each line, annunciators normally connected in said lines, switch plugs and cords for connectin g difierent spring-jacks, visual signals, as glow-lamps, for indicating lines that are in use, circuit connections for the visual signals, means operated by the falling of either of said annunciators to operate the corresponding visual signal, means at the springjacks and operated by inserting the plugs for operating, or maintaining the operation, of said visual signals independently of said annuneiators.

3. The combination of telephone lines, multiple switchboards therefor, there being a spring-jack at each board for each line, a calling-annunciator for each line at one of the boards, a single electric indicating-lamp for each line to show whether the lines are busy or free, said lamps being massed separate from the spring-jacks in sight from all the sections of said multiple switchboard, circuits for said lamps, circuit-control1ing contacts or circuit-closers operated by the annunciators, and circuit-closing springs therefor operated by insertion of a plug in a jack.

4:. The combination of telephone P lines, multiple switchboards therefor, there being a spring-jack at each board for each line, a calling-annunciator for each line at one of the boards, a single electric indicating-lamp for each line to show whether the lines are busy or free, said lamps being massed separate from the spring-jacks in sight from all the sections of said multiple switchboard", two-independent circuit-controlling devices forthe circuit of each lamp at one section of the switchboard andone' circuit-controlling device for the same circuit at each other-section, and numbers corresponding to the jacks illuminated by said lamps.

In testimony whereof I have affixed my signature in presence. of two witnesses.

JULIUS IIENRIK VEST.

Witnesses MAX WAGNER, E. KoLLINER. 

